Fix tests

[j-maas]

No description provided.

[j-maas]

I used type hints, so the tests only pass in Python 3.6.

[codecov]

Codecov Report

Merging #13 into master will decrease coverage by 0.21%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master      #13      +/-   ##
==========================================
- Coverage   99.68%   99.46%   -0.22%     
==========================================
  Files          11       11              
  Lines         939      941       +2     
==========================================
  Hits          936      936              
- Misses          3        5       +2

Impacted Files	Coverage Δ
ptbtest/usergenerator.py	100% <ø> (ø)	⬆️
ptbtest/mockbot.py	99.48% <100%> (ø)	⬆️
ptbtest/messagegenerator.py	99.28% <0%> (-0.72%)	⬇️

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[j-maas]

Sorry for the noise, will PR from a branch, not my master...